Sedative hypnotics, acute actions

Ethanol A sedative-hypnotic. Acute actions include impaired judgment, ataxia, loss of... 

Meperidine (Demerol) [C-ll] [Narcotic Analgesic] Uses Moderate/ severe pain Action Narcotic analgesic Dose Adults. 25-50 mg IV, 50-100 mg IM Peds. 1 mg/kg IV/IM (onset w/in 5 min IV and 10 min IM duration about 2 h) Caution [C, ] Contra Convulsive disorders and acute abdomen Disp Prefilled 1 mL syringes 25, 50, 75, 100 mg/mL various amps and vials oral syrup and tabs SE N/V (may be severe), dizziness, weakness, sedation, miosis, resp d ession, xerostomia (dry mouth) Interactions t CNS depression W/ opiates, sedatives/ hypnotics TCNS stimulation W/amphetamines t risk of tox W7 phenytoin EMS Pt should be receiving O2 prior to administration have resuscitation equipment and naloxone available naloxone can be used as an antidote to reverse resp depression aspirate prior to IM administration inadv tent IV admin of IM doses may cause tach and syncope mix w/ NS to make a 10 mg/mL soln and inj very slowly N/V may be sev e may premedicate w/ an antiemetic... 

The acute effects of ethanol and other sedative-hypnotics are mediated by actions at a number of receptor systems. For example, ethanol inhibits several excitatory receptor systems, including N-methyl-D-aspartate (NMDA) receptors, kainate receptors, and Ca channels. In addition, ethanol enhances the action of GABA at GABA receptors and appears to modulate serotonergic neurotransmission. Although a component of ethanol reinforcement is mediated by the activation of mesocorticolimbic dopamine neurons, activation of these neurons may not be necessary for ethanol reinforcement, as ethanol remains reinforcing in the absence of these neurons (Samson and Harris, 1992 Koob, 2000b). 

Knowing the differential pharmacokinetics for a class of drugs allows the clinician to choose specific members to either achieve a faster onset or a delayed offset of action (13, 14, 17, 18). For example, lorazepam is rapidly absorbed from the gastrointestinal tract into the systemic circulation and from there distributed into the brain. In contrast, oxazepam, the most polar BZD, is slowly absorbed from the gastrointestinal tract. Even after oxazepam is in the systemic circulation, it slowly enters tissue compartments, including the brain, during the distribution phase. Unlike lorazepam, oxazepam is not available in either the intramuscular or intravenous formulations. Thus, lorazepam would be preferable to achieve acute control of alcohol withdrawal (e.g., delirium tremens), whereas oxazepam would better stabilize a dependency-prone patient on sedative-hypnotics, because it does not cause the euphoria seen with the more rapidly absorbed members of this class. 

Kava is most often used as a sedative-hypnotic to treat anxiety. The substance has been evaluated in Europe and in the USA for the treatment of anxiety in several placebo-controlled studies. Most of these trials have shown significant improvements in anxiety symptoms in patients with moderate to severe anxiety within 8 weeks after starting treatment. In one study, kava was compared with oxazepam, a benzodiazepine. Similar reductions in anxiolytic effects and fewer adverse effects were reported for the kava group. Kava appears to have a slow onset of action for the treatment of anxiety symptoms, most patients responding only after 4-8 weeks. Kava should not be used to treat acute symptoms of anxiety or panic attacks. 

Ethchlorvynol, USP. Ethchlurvynol. l-chloro-.A-cthyl-l-penten-4-yn-.A-ol (Placidyl). is a sedative-hypnotic with a rapid on.sct and short duration of action. Metabolism, probably involving the hydroxyl group, accounts for about 90% of a dose. Acute overdo.se shares several features with barbiturate overdose. 

An acute action of melatonin of much interest is a sedative activity not mediated by an interaction with benzodiazepine or cannabinoid receptors. There is hope of developing a new type of hypnotic agent from this approach. A rather different aspect, potentially of great importance, is the use of melatonin analogues for re-establishing the circadian sleep rhythm when this is disturbed e.g. jet-lag, in the elderly and in disease (e.g. Alzheimer s disease). 

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